Are there any issues or concerns with planting a few yews or cedars along the edge of a veranda? I live in Cabbagetown, Toronto and although we have been fortunate to not have any, there have been termites in the neighbourhood and we’d like to avoid planting anything that would encourage them. For this reason, I have avoided laying cedar mulch this year near the house. Are there any other factors we should consider when planting shrubs and plants on our property to deter (or not encourage) these little creatures from visiting? Is there anything plant or shrub that could be planted as a deterrent?
A number of trees such as cedars and yews have a resistance to termites because they produce a resin toxic to termites but it is the heartwood of the tree that has the most resistance. Eastern Subterranean Termites which are the main problem termite in Toronto “can occasionally feed on trees, but it is usually only dead trees or dead parts of trees…”. The City of Toronto fact sheet also points out that living trees have not been proved to be a source for termite infestations so it should be safe to plant the trees. The best defense to protect the trees from termites is to ensure that they are healthy with no dead wood.
Lumber made from termite resistance trees also has some resistance to termites but this is reduced as the essential oils in the lumber dry out. Therefore while cedar mulch has some termite resistance but it will not last. The mulching is recommended to help prevent your trees from drying out but it may also provide a moist environment for termites so keeping it away from the house is a good strategy.